Having kept close track not only of the numbers, but of the hours, each count being made to cover five minutes, we were able to calculate that an average trip occupied forty–three minutes. When we met these wasps in the garden they never seemed to be hurrying, and had the air of amusing themselves; but they must be faithful workers to accomplish so much. The curious fact has been established that when food is very plentiful the workers begin to lay male eggs, thus taking from the queen a part of her burden and leaving her free to produce neuters and females. The nest that we were watching was found, at the end of the season, to contain 4661 wasps in various stages of development, and others that we opened had from two to four thousand. This is nothing to the social wasps of China, where a single household is made up of from fifteen to twenty thousand members; but China is a thickly populated country, and perhaps with wasps as with human beings several families live in a single domicile. Outside of their wonderful social instincts our wasps are found wanting in the higher gifts of emotion and intellect. When we killed a number of them and placed them near the nest, their nearest relatives wasted no time in mourning, nor yet in revenge, but calmly cut up the bodies and fed them to the ever hungry young ones. If we placed some rich and tempting morsels at a distance, two or three would discover them, and would go back and forth all day without telling the others about it, as ants would have done under like circumstances. When we obstructed the opening to their nest by lightly laying blades of grass across, the day passed without its occurring to the wasps to lift them away, although they suffered the greatest inconvenience in getting in and out, crawling laboriously through, and in some instances giving up the task and flying away. Vespa maculata, building on trees and fences, has practically the same habits as the ground wasp, germanica, the internal structure of the nest following the same plan, while the outer wall is of a papery substance like that of the combs, made from the scrapings of weather–beaten wood. The genus Polistes builds combs similar to that of Vespa, under porches or in any sheltered place, and does not inclose them. All these wasps, when adult, enjoy fruit and flowers as well as animal food; but only this last is used for the young, and many a caterpillar creeping along with sinister design is snatched by them to be chewed into a pulpy mass, and then fed to the larvæ. No calculation has been made of the value of these wasps in agriculture, and one of the things that farmers have yet to learn is to encourage their presence in orchards and gardens.